Alkyl ethers of cellulose and proces of making the same.



UNITED STATES PATENT OFFICE. l'

LEON LILIENFELD, OI VIENNA, AUSTRIA-HUNGARY.

1,188,376. No Drawing.

To all whom it may concern:

dic'it known that I, Dr. LEON LILIENFELD, a subject of the Emperor of Austria-Hungary, residing at No. 1 Zeltgasse, Vienna, VIII, Austria-Hungary, have invented new and useful Alkyl Ethers' of Cellulose and Process of Making the Same, of which the following is a specification.

The present invention relates to the manufacture of new cellulose derivatives which are chemically alkyl ethers of'cellulose that is, compounds of cellulose or of its allied conversioh roducts such as cellulose hydrate, oxy-ce lulose and the like, in which one, several or all of thehydro en atoms of the hydroxyl roups of'the cellulose are replaced ,by a kyl radicals or, in

. other words, in which cellulose has been bined with favorable solubilities and very valuable physical properties, render the said bodies suitable for a very great variety of uses.

The process consists in first treating cellui, lose or its convcrslon products or dcrlva- 1 tives with suitable alkylatmg e ents and thus substituting the corres )onding alkyl radicals for one, several or al of the hydrm genatoms of the hydroxyl groups of the cellulose, and secondly isolating the formed alkyl ethers of cellulose from the reaction mixture.

The following raw or primary materials may be employed:

1. Bleached or unbleached cellulose in any form. v

2. Substances or materials containing cellulose, for instance, wood, pulp, cotton, flax, hemp, jute, straw, esparto, rice husks, vegetable pith and the like.

3. Conversion-products allied to cellulose, for instance hydrolyzed and oxidized celluloses (such as cellulose hydrate, cellulose acid-cellulose, sulfhydro-cellulose, colloida cellulose,oxy-cellulose,celloxin and the like), which are gbtalned by treating cellulose, or materials containing cellulose, with peroxwith the aid of heat, &c.

. J v ALKYL ETHEBS OF GELL'ULOSE AND PROCESS OF MAKING THE SAME.

Specification of Letters Patent. I. Patented J ne 20, 1916. Application tlled June as, 1012. Serial No. 700,009.

ids, pcrborates, persulfates, percarbonates, permanganates chromic acld, bichromates, nitric acid, ch orid of lime, hypochlorites and by )obromites, chlorates in acid solution, ch lorin and bromin alone or in the presence of inorganic or organic acids, sulfur ch-lorid, oxygen, ozone, cuprammonium solution, ammomacal cuprous oxid solution, zinc chlorid and other zinc halids, organic and inorganic acids, alkalis in the cold or To this third class belong the cellulose derivatives that are soluble in aqueous solutions of alkalis and are very suitable ior the present process, in the form in which they are obtained by treating cellulose with hot alkaline liquors (with or without subsequent precipitationlb means of acids, alcohols and the like), with cuprammonium solution and subsequent precipitation b suitable precipitants, such as acids, alka is, salts and the like, with zinc halids alone or in conjunction with acids and subsequent precipitation, with strong sulfuric acid (6. g. 45 to 60 B.) and subsequent precipitation by dilution with water. For this purpose .there ma also be used the cellulose conver-' sion pro ucts soluble in solutions of alkalis which are produced by the action of saponitying agents upon their esters (cellulose nitrates, cellulose acetates, cellulose format-es and the like) and those which are produccd by treating raw or refined cellulose xanthogenates (viscose) with acids, metallic salts, acids andsalts, heat, spontaneous coagulation, and the like. The cellulose xanthogenates are also suitable in whateverform they occur. Artificial silks and artificial silk waste of all kinds (for instance nitro-cellulose silk, viscose silk, silk obtained from cellulose dissolved in cuprammonium solution, acetyl-cellulose silk, formyl-cellulose silk, &c) may. therefore also be used in the new n-ocess.

4. All lnorganic and organic simple and mixed esters of cellulose, for instance, nitro-' celluloses, acetyl-celluloses, formyl-celluloses, lactyl-celluloses, cellulose phosphates, formyl-cellul ose phosphates and the like. If basic substances are present in the reaction mixture, thenin most cases a saponification of the hereinbefore mentioned esters will take place. The resulting salts of the acid components of the esters have no pronounced unfavorable influence on the reaction. Consequently the cellulose or cellulosehydrate which is liberated at the same time reacts exactly in the same manner, and pro duces exactly the same alkali ethers as OI'dlnary cellulose or cellulose-hydrate. In case of the saponification of the cellulose-esters" means those bodies referred to in the fore-- going paragraphs 1, 2, 3 and 4.

he process may be carried out for 1nstance by first treating cellulose or its conversion products or derivatives of cellulose with basic substances and inorganic alkyl esters and secondly isolating the formed alkyl ethers of cellulose from the reaction mixture. Alkyl halids, sulfuric acid esters, alkyl sulfates, etc., in short, suitable inorganic alkyl esters generally may be caused to act upon cellulosic substances such as cellulose or its derivatives or conversion products. If the alkali compounds of cellulose (mercer ized cellulose) cellulose-hydrate, oxy-cellulose, cellulose-xanthogenates or the like, or other existing metallic compounds of cellulose are employed as primary materials, then the basic substances are fixed to thecellulose In all other cases the basic sub-, stances are introduced in a free state into bodies.

the reaction mass. The process may, however, be carried out by adding to the reaction mixtures a further quantity of free basic substances, for instance alkalis alkali-alcoholates and the like, in 'addltion to .the basic substances fixed to the cellulose bodies. The desired amount of basic substances may be added to the reaction mixtures either all at once at the beginning or gradually during the reaction. They may be added in the undissolved state, or dissolved in suitable solvents.

The process may also be carried out in the presence of basic substances in excess, and

the excess of basic substances (especially if caustic alkalis) may also act as condensing or dehydrating agents.

The cellulosic substances such as cellulose, cellulose derivatives or cellulose conversion products, may be employed dissolved in suitable solvents, or undissolved. For instance, if the primary materials employed. are the cellulose-hydrates, oxy-celluloses, cellulose xanthogenates, colloidal celluloses and the like or their metallic compounds, which are soluble in water or in aqueous alkalis, am-

monia and the like, the reaction may be effected in anagueous or aqueous-alkaline or aqueous-alcoho ic solution. Or the operations may be begun with an aqueous-alkaline solution, and an organic solvent or diluent,

for instance an alcohol, hydrocarbons, pyridin or the like may be added during the re areaeae I action either in one portion or in several ortions. These solvents or diluents (for instance alcohol) may also be employed for dissolving. the basic substances (for instance, an alka i metal. hydroxid, alkali-metal, alkali-alcoholate ammonia, pyridin and the like). When the primary materials employed are cellulose derivatives (for instance cellulose esters and the like) soluble in orgame solvents, they may be dissolved in organic solvents such asalcohol, pyridin and the like, and thus brought into the reaction.

The process may also be commenced with undissolved cellulcsic substances especially 1n cases where one has to deal with insoluble cellulosic substances such as cellulose, alkalicellulose, alkali-insoluble cellulose-hydrate, alkali-insoluble oxy-cellulose and the like.

In all cases, in working with dissolved or with undissolved cellulosic substances, the reaction may be carried out in the presence or in the absence of diluents or of solvents for the, resulting a1 1 ethers of cellulose (for instance, alcohol, enzene,pyridin and the like). When for instance pyridin or similar bases are employed as solvents or diluents, they may also act as basic substances. The inorganic alkyl esters may be added either at once or gradually to the reaction mixtures. take place in an open vessel or in a vessel provided 'with a reflux condenser or under pressure (for instance in digesters, autoclaves, pressure tubes and the like) or in a partial vacuum, orwith exclusion of air by means of neutral gases. In most cases the alkyl ethers of cellulose may be preferably separated out from aqueous reaction mixtures by bringing the hot or warm reaction masses either directly or after dilution with water, or when necessary after previous neutralization or acidification, on to filters, filter presses, suction apparatus, percolating cloths, centrifugal apparatus, rotary filters or the like, and washing the precipitates thoroughly with hot water. If the resulting alkyl ethers of cellulose are also insoluble in cold water they maybe freed by means of cold water from the by-products of the reaction. If the resulting alkyl ethers of cellulose are contained. in the dissolved state in the reaction mixture, as would be the case when the reaction has taken place in the presence of a solvent, they can be precipi-. tated by the addition of hot or cold water or aqueous solutions of salts. In all cases they-can be removed from the reaction mixtures by a suitable extracting agent in which they are soluble and the by-products of the reaction are insoluble. They can then be obtained either by precipitation b suitable precipitants, or by drivin ofi' t e solvent. If necessary the alkyl et ers of cellu- The reaction may process, conveniently by redissolving them in a suitable solvent and then precipitating by means of a suitable precipitant or by dialysis or bydistilling off said solvent or the like.

Since as is well known, cellulose contains several alcoholic hydroxyl-hydrogens the new process permits of varying from the beginning the number of the hydrogen atoms of the hydroxyl groups of the cellulose that are replaced by a1 yl radicals. The number of the introduced alkyl radicals depends upon the quantity of the inorganic alkyl esters which is em loyed and also on the'condit ons of wor in (temperature, nature and quantity of the asic substances, concentration of the reaction mixtures, etc.)

Alkyl ethers of cellulose containing several alkyl radicals may also be produced by preparing alkyl ethers with a lower number of alkyl-radicals and thereafter treating them with inorganic alkyl esters. I'-

The free hydroxyl groups of those alkyl ethers of cellulose in which not all of-the hydrogen atoms of the hydroxyl'groups of the cellulose or of its converslon products are replaced by alkyl radicals, have-a natural tendency to form compounds with basic substances andespecially with metals, for instance, alkali metals, or their hydroxids. This is shown for instance by the fact that many alcoholic-soluble alkyl ethers of cellulose in which not all of the hydrogen atoms of the hydroxyl groups of the cellulose are replaced by alkyl radicals, yield precipitates when their alcoholic solutions are treated'with a solution of an alkali in alcohol. This is due to the fact that although the free alkyl ethers of cellulose are soluble in alcohol, yet their compounds with alkalis are insoluble in alcohol. For this reason in the case of such alkyl ethers of cellulose it is advisable to liberate the hydroxyl group by treating such alkali compounds with acids or acid salts. This may be done either by adding substances having an acid reaction to the reaction mixtures after the completion of the reaction or by separating out the compounds of the alkyl ethers of cellulose with the basic substances and then subjecting them to the action of acids or acid salts.

It appears probable that in many cases mixtures of various alk l ethers of cellulose are produced instead 0 a single alkyl ether of cellulose. In these mixtures t e substances may difi'er from-each other in that they contain difi'erent numbers of alkyl radicals. Mixed alkyl ethers of cellulose are produced by allowing two or more inorganic alkyl esters -(diflering from one another as regards the alkyl-radicals) to act upon cellulosic substances for example cellulose or its conversion products or derivatives. Such mixed alkyl-ethers of cellulose may also be obtained by producing alkyl ethers containing free hydroxyl groups and containing one or more introduced similar alkyl radicals,' and then treating them with inorganic alkyl esters containing one, or

cellulose produced according to this inventionhave the characteristic feature that although they are soluble in cold water, they are insoluble or diflicultly soluble in hot water, so that theiraqueous solutions become coagulated or precipitated by heating. Many of the water-insoluble cellulose ethers are soluble in a surprisingly large number of solvents.

According to my researches the alkyl ethers of cellulose have all in common an extremely high degree of stability, neutrality and indifierence. heated alone .or with water and are characterized by the fact that they are not decomposable b aqueous or alcoholic solutions of alkalis. his test readily distinguishes the alkyl ethers of cellulose from the cellulose esters. The alkyl ethers of cellulose possess a greater stability than any of the simple or mixed cellulose esters or any of the hitherto described conversion roducts or derivatives of cellulose. The alliyl ethers of cellulose yield alk l iodids on being treated with concentrate hydriodic acid. All alkyl ethers of cellulose have accordin to my researches further in common that ii ms, coatings, filaments, plastic masses and products generally produced from their solutions or jellies possess a very remarkable degree of suppleness, flexibility,- power of resistance to chem- .ical and physical influences, hardness and strength. All these advantages are further accompaniedby the property of many alkyl ethers of cellulose of being readily and easily soluble in an almost unlimited number of solvents, which is a property which has not been possessed hitherto, by any conversion roduct of cellulose or derivative of celluose. Finally the alkyl ethers of cellulose are distinguished by their uninflammability or only very slight combustibility. All those properties render the alkyl ethers of cellulose suitable for a practically unlimited number of uses. Above all, they are according to my researches, adapted with regard to the above mentioned properties to replace with advantage in the same or similar applications, ccllulose and its conversion products They withstand being of combining the .alkyl ethers 0 and derivatives (cellulose hydrate, oxy-cellulose, viscose, nitro-cellulose, acetyl-cellulose,

formyl-cellulose, etc.).

Owing. to the very numerous solvents in which the alkyl ethers of cellulose are soluble, these compounds may be combined with a much larger number of softening and gelat inizingagents than has been possible in the case of the cellulose derivatives hitherto known. The great number of solvents available therefore provides also the ossibility f cellulose with many other colloids and binding substances and plastic bodies with which the hitherto known cellulose derivatives could not be combined. Since the series of solvents, beginning with water,'comprises almost all the organic solvents it is possible to combine the various alkyl ethers of cellulose with many water-soluble colloids,

' binding substances, thickening agents, plastic bod1es,'drying andnon-drying oils, fats, balsams, adhesives, waxes, parafims, resins, caoutchouc and gutta-percha, etc.

known cellulose derivatives, such as viscose, cellulose, hydrate, oxy-cellulose, cuprammonium-cellulose, nitro-cellulose, formyl-cellulose, acetyl-cellulose, etc. One and the same solvent (simple or mixed) may be used for said substances and. for the corresponding alkyl ethers of cellulose.

It would take too long to'enumerate in this specification all the uses for which the cellulose alkyl ethers are suitable. The fol lowing uses may be mentioned by way of 1 example :-as plastic masses, celluloid substitutes (alkyl ethers of cellulose, alone or mixed with-other cellulose derivatives or mixed with camphor or other gelatinizing agents, or camphor substitutes, or agents for vention is not limited to these particular exam les:

I. a) 3750' parts by weight of a raw viscose containing about '500 parts by weight .of cellulose and about 130 to 200 partsby weight of caustic soda, are diluted with 3750 parts by weight of water, and heated with stirring on the water bath until complete coagulation has taken place. The coagulated mass which has crumbled into small lumps by the stirring, is thoroughly washed in They, may be worked together with the hitherto areas-re v flowing water, crushed, pressed to 5000 parts by weight, and then dlssolved in 1000 parts by weight of a caustic soda solution of 50 percent. strength; The solution may then be freed b filtering or percolation from any particles tliat have remained undissolved.

(b) Cellulose hydrate is precipitated by dilute sulfuric acid from a solution of cellulose in Schweizers reagent, and is dissolved in caustic soda solution sot-hat 120 parts of the solution contain 10 parts of cellulose cellulose hydrate and 10 parts of caustic soda. I

The expression primary solutions as in Example I, used in several of the following specific examples is intended to refer to the solution as prepared according to either one of the above paragraphs I 0;, I b, or li a.

1200 parts by weight of the solution resulting from the treatment given under (a) (b) or (0) containing 100 parts by weight of cellulose or of cellulose hydrate, as the case may be, and 100 parts by weight of caustic soda are mixed with 100 to 400 parts by weight of caustic soda solution of 30 per .cent. 'strengthil well stirred and gently warmed. To t is are then added 200 parts by weight of di-ethyl sulfate in small portions, and the mixture is again heated for a time if required. The turbid reaction mass is diluted with hot water and acidified with dilute sulfuric acid, the resulting ether being thus separated out. lit is preferably collected on a hot water funnel and thoroughly washed with hot water. The washed ethyl ether of cellulose is then dried in a vacuum or in air with or without the aid of heat, either immediately or after treatment with alcohol or alcohol and ether, or it is subected if desired .to a purifying process. This purifying process may conslst in, for instance, re-dissolving in cold water and prec1p1tat1on by alcohol, or by heatingalone or in the presence of salt solutions. The resulting ethyl ether of cellulose is a white, pulverulent or flaky substance which is readily soluble in cold water, formic acid,

cold or-hot aqueous acetic acid and aqueous 4 pyridin, but 1s insoluble in alcohol and in hot water. 7

1200 parts by weight of one of the primary solutions as in Example 1, containmg 100 arts by weight of cellulose or cellulose hy rate, and 100 parts by weight of caustic soda, are heated with 100 to 400 parts by weight of caustic soda solution of 30 if re lured. The reaction mass is acidified by stirring, shaking, kneading or rubbing the mass withdilute sulfuric acid, collected on a filtering device and thoroughly-washed wlth hot water. The further treatment is as described in Example I. The resulting ethyl ether ofcellulose is a white pulverulent or flaky substance which is readil soluble in cold water, glacial accticiacid, ormic acid pyridln, di-chlorhydrin, ethyl formate and aqueous acetone, but is insoluble in hot water.

III. 1200 parts by weight of one of the rimary solutions as in Example I, contain- 1ng'100 parts by weight of cellulose and 100 parts by weight of caustic soda, are heated with 200 to 00 parts by weight of a caustic soda solution of 30m -10 per cent.

strength, and then 500 parts by weight of di-ethyl sulfate are. added gradually, the

reaction temperature rises and the cellulose ether separates out. It may either be collected immediately on a filtering device and washed with hot water and then treated with 'an acid, or the whole reaction mass may be acidified by well stirring, shaking or kneadin it with dilute sulfuric acid, then filtered and afterward washed. The final preparation of the ethyl ether is effected as in Example I. Since however this other is soluble in alcohol, it may be purified by dissolving .in alcohol and precipitating by, ether, benzene or the like. This ethyl ether of cellulose is a white nilverulent or flaky substance which is reac ily soluble in cold-water, alcohol, methylalcohol, glacial acetic acid,'formic acid, pyridin, di-chlorhydrin, nitro-benzene, ethyl formate and aqueous acetone, but isinsoluble in hot water. 4

IV. 1200 parts by weight of one of the primary solutions as in Example I, containing 100 parts by weight of cellulose and 100 parts by weight of caustic soda, are mixed with 500 parts by weight of di-ethyl sulfate heated and mixed gradually with 220 parts by weight of caustic soda solution of 30 per cent. strength, or with the equivalent quantity (if an alcoholic caustic potash solution of 25 per cent. strength.- If necessary the mixture may thenbe heated. In this case also the treatment may consist in diluting immediately with hot water, filtering, and washing the ethyl ether of cellulose remaining on the filter, and then subjecting it to a subsequent treatment wlth an acid, or in acidifyingthe reaction mixture after the end of the reaction with for instance dilute sulfuric acid, when the reaction 1s complete, filtering and thoroughly washing the precipitate. The final prepaequivalent quantity of a strong alcoholic fate. after a certain lapse of time, 500 parts by mixed with 500 parts by weight-of di-ethyl sulfate, heated and gradually mixed with 130 to 220 parts by weight of caustic soda solution of 50 per cent. strength, or the caustic potash solution. The mass is afterward heated if required. The further treatment is as in Examples III and IV. The resulting ethyl ether of cellulose is a white pulverulent or flaky substance which is readily soluble in cold water, alcohol, methyl-alcohol, glacial acetic acid, formic acid, pyridin, di-chlorhydrin, nitro-benzene, ethyl formate,-aqueous acetone, elatinizes in tetra chlorethane and is insolu le in hot water.

VI. 1200 parts by weight of one of the primary solutions as in Example I, containmg 100 parts by weight.- of cellulose and 100 parts by weight of caustic soda, are mixed with 110 parts by weight "of caustic soda solution of 30 per cent. strength, heated. and then 166.6 parts by weight of dicthyl sulfate are added. After about half an hour another 110 parts by, Weight of 30 per cent. caustic soda solution and another 166.6 parts by weight of di-ethyl sulfate are added, and the same additions are again made after the lapse of another half hour, so that the total addition consists of 333 parts by weight of 30 per cent. caustic soda solution and 500 parts by weight of di ethyl sulfate. The mass is again heated 1f required and further treated as in Examples III, IV and V. The resulting ethyl ether of cellulose is a white pulverulent or flaky. substance which is soluble in cold water, alcohol, methyl-alcohol, formic acid, glacial acetic acid, pyridin, dichlorhydrin, mtro-.

but is, insoluble in hot water.-

VII. 1200 parts by weight of one of the rimary solutions as in Example I, contammg 100 parts by weight of cellulose and 100aparts by weight of caustic soda, are mixed with 625 parts by weight of caustic soda solution of 40 per cent. strength, gently heated, and then there are gradually added 600 to 750 parts by weight of di-ethyl sul- Immediately after this addition or weight of 50 per cent. caustic soda solution and 600 to 750 parts by weight of di -ethyl I sulfate are added. The separation of the 180 benzene, ethyl formats and aqueous acetone,

, water.

100 parts by weight 0 mixed with 100 parts byweight of a 30' ethyl ether of cellulose is accompanied by a rise in temperature and fro'thing of the mass. The reaction mixture is preferably after dilution with water, either acidified immediately with dilute sulfuric aeid or placed inthe alkaline state on a suitable filtering device, and the ethyl ether of cellulose isthoroughly washed with hot or cold In the second .case it is preferred to efiect a subsequent treatment with an acid or with an acid salt, and again washing. The resulting ethyl ether or cellulose isinsoluble in either hot or cold water, and may per cent. caustic soda solution, and gently heated, and there arethen added gradually 100 to 200 parts by weight of di-ethyl sulfate. The addition takes about say, from half an hour to two hours. The product at this stage of the process consists essentially of cellulose ethers in' which a relatively small number of hydroxyl hydrogens have been replaced by alcohol radicals, and the material is somewhat soluble in water, and is more soluble in cold water than in hot.

If necessary. the mass is afterward heated V vents :alcohol, methyl-alcohol, glacial aceon the water bath for half an .hour totwo hours and the reaction mixture, preferably when cold, is rubbed up, stirred or kneaded with 300 to 600 parts by weight of powdered caustic soda or the equivalent quantity of caustic potash. The caustic potash or caustic-soda, in the form of a powder, appears to act as a dehydrating agent. Then the mass is again heated and into it are'introduced 300to 1300 parts by weight of di ethyl sulfate gradually or in several portions at suitable intervals of time, where-' upon the separation of the ethyl ether of cellulose takes place accompanied by a rise in temperature and frothing of the mass. The reaction mixture is preferably after dilution with water, either acidified immediately with dilute sulfuric acid, or is placed in the alkaline state upon a suitable filter- I the like, nitro-methane,- phenyl ing device, and the cellulose ether collected on the filtering device is-jthorou'ghly washed with hot or cold water. In the second case it .is preferred to efiect a subsequent treatinsects washing.

Since those conversion productsor derivatives of cellulose which are soluble in aqueous solutions of alkalis are separated out or precipitated when adding a larger quantity of'caustic alkali and more es ecially on heating, the operation in the xamples VII. and-VIII is, as will be seen, carried out in such a manner that I add first only part of the amount of caustic soda and of the ethyl sulfate which would be necessary to obtain the insoluble ethyl cellulose or ethyl cellulose hydrate so that ll obtain first a water soluble ethyl cellulose; thereafter I add to the reaction mixture containing the water soluble ethyl cellulose a further quantity of caustic soda and ethyl sulfate, thu transforming the water soluble ethyl ether of cellulose into an insoluble ethyl ether. It is evident that the reaction between the alkyl-sulfate andthe alkali hydroxid may also be carried out by adding the one and the other in a greater number of portions, alternating in such a manner that each addition of a small portion of alkali hydroxid is followed by the addition of a small portion of ethyl sulfate. -Tt is,

.of course, clear that the .water soluble ether may be separated out and treated after sep-' aration with a further quantity of an'alkali and of ethyl sulfate in order to convert it into an insoluble ether. Since. the' final ethyl ether of cellulose is insoluble in water, it may be purified, say, bydissolving in alcohol and then with orwithout filtration,

precipitating by water or a dilute salt solution, and again washing. The resulting ethylether of cellulose'is a white powder which is 'inso'luble'in'hot or cold water but is readily soluble in the following soltic acid, formic acid, pyridin, quinolin, picolin, dichlorhydrin, epi-chlorhydrin and the like, nitro-benzene', methyl-acetate, acetic ether, ethyl phthalate, ethyl sebacate, ethyl citrate, ethyl sucinate, ethyltartrate, amyl-acetate, butyl-acetate, ethyl benzoate, ethyl levulinate and the like, acetone, pentachlorethane, tetrachlorethane, trichlorethane, acetylene, =di -chlorid, carbon tetra chlorid, chloroform and the like, benzene, toluene, xylene, phenol, nitrophenols, o'rthocresol and vthe like, naphthalene, toluidin, anilin and the like, forinanilid, acetanilid and the like, turpentine oil, camphor, castor oil, linseed oil, Chinese Wood oil, olive oil and the like, vaseline oil, paraffin oil, naphtha (petroleum), Vaseline and the like, stearin, beeswax, Japan wax, lanolin and ether, tritri-cresyl phosphate,- etc.

phenyl phosphate,

soluble in' a mixture of It is also readily ethyl-alcohol and etheryand also in ethyl.

other alone, but not so readily in the latter. It can withstand being heated for days 1n digesters in the presence of water at hi h temperatures, such as for instance 170 egrees 0. without showing any alteration. It can be heated for several days with 25 per cent. queous caustic soda solution and also with 25 per cent. alcoholic caustic potash solution without undergoing decom osition or change. The combustion -o a purified sample of a particular product, made in accordance with this example, dried at 105 degrees C., until its weight remained uniform and containing 0.19 per cent. of

ash, gave. the following results (a) 0.1970 grams of the sample (calculated for matter free from ash) gave 0.1562 gms. H O=8.80 p. c. of H' and 0.4091 gms. CO,=56.67 per cent. of C..

(1)) 0.2134 gms. of the sample (calculatedfor matter free from ash). gaved 0.1719 gms.v H 0- 8.95-p. c. of'H, an

0.4422 gms. CO =56.51 p. c. of C.

Calculated for 22 4 o 1o ia rs m- 2 5) 5 56.89 p. c. of C, 8.62 p. c. of H.

From the ultimate anal sis, the new sub stance would appear to he a penta-ethylether of cellulose. The invention is not however, limited to this particular example, since 'various other products can be made, in accordance with the present invention, which do not have this analysis.

IX. 1200 parts by weight of one of the primary solutions as in Example I, containing 100 parts by weight of cellulose and .100 parts by weight of caustic soda, are

mixed with 520 to 800 parts by weight of a 30 per cent. caustic soda solution and 1000 parts by weight of ethyl. iodid, and heated for some hour's to 100 degrees C. in a digester. The resultis a somewhat viscid liquid in which is suspended a precipitate if readily soluble in alcohol, methyl-alcohol,

chlorhydrin, formic acid, glacial acetic acid, nitro-benzene, aqueous acetone, carbo tetrachlorid and the like.

X. 1200 arts by weight of one of the primary so utions as in Example I, containing 100 parts'by wei ht of cellulose and 100 parts by weight oi caustic soda, are heated with 520 to 600 parts by weight of a 30 per cent. caustic soda solution with reflux-cooling, and then 1000 arts by weight of ethyl-iodid are added all at once or in several portions. After protracted heatin the ethyl-ether of cellulose separates out-an is then treated further as in Example IX, its properties being identical with those of the ethyl-ether produced according to Example IX. Working with other ethylhalids, for instailce ethyl-bromid and ethylchlorid is similar; their low boiling points having however to be taken into consideration.

Instead of using the cellulose hydrate mentioned in the foregoing examplesthe same result may be obtained by treating any other cellulose hydrate or oxy-cellulose.

'XI. 750 parts by weight of a soda-cellulose (prepared by impregnating cellulose with strong caustic soda solution, squeezing, and then triturating) containing 250 parts by weight of cellulose and 250 parts by weight of caustic soda, are rubbed up with 310 parts by weight of a-10 per cent. caustic soda solution and mixed and heated with 1000 to2500 parts by weight of di ethyl sulfate. After the completion of the reaction,

which takes place with frothing. the reaction mixture 1s placed on a filter and the ether remaining on the filter is washed with 7 hot water. The separated ether may be purified by dissolving it in alcohol and precipitating it by ether, benzene or the like.

It is a white powder which is soluble in cold water, alcohol, methyl-alcohol, glacial acetic acid, formic acid, py'ridin, nitro-benzene,

and aqueous acetone; it 'gelatinizes in tetrachlorethane, and is insoluble in hot water.

Ethyl ethers of cellulose which 'are insoluble in cold water apd are. readily soluble in volatile solvents may be produced from alkali-cellulose by varying the conditions of working.

XII. 1200 parts by weight of one of the primary solutions as in Example I, containmg 100 parts by weight of cellulose and 100 parts by weight of caustic soda, are mixed with 100 parts by Weight of a1 30 per; cent.- caustic soda solution and gently heated, and then 200 parts by weight of di-ethyl sulfate are introduced gradually. After this addition, and if necessary after" again heating; 1

the mixture is rubbed up with 300 to 600 parts by weight of powdered caustic soda,

I the reaction mixture is again heated and to it are then added 200 parts byweight of potassium ethyl sulfate or the equivalent quantity of sodium ethyl sulfate in: small.

portions at a time. The further treatment methyl-ethers however differ in their prop- I erties from the hereinbefore describeclethylothers of cellulose. I

It is to be understood, that although the examples given above relate specifically a) the production of ethyl ethers of cellulose, the invention is not limited thereto, since other'alkyl radicals may be substituted instead of the ethyl roup. I also call attention to the fact t at the term cellulose ethers .has heretofore been incorrectly applied, to celluloseesters, such as cellulose acetate and cellulose nitrate, but I desire to call attention to the fact that the term cellulose ether as used in this specification, and in the claims hereto annexed is not intended to apply to esters, but to ethers, that is to say bodies derived from alcohols, by the substitution of an alkyl radical, in place of a hydroxyl hydrogen atom;

Mixtures including cellulose ethers and softening agents or agents capable of increasing the plasticity or other conditioning agents, are not' specifically claimed herein, althoughincluded within the scope of certain of- .the claims.- Such mixtures are specificallyclaimed'in my copending applications as follows :754333filed March 14,

.1913 and 796248 and 796249 filed October Having now described my invention what I claim as new and desire to secure by Letters Patent is:

1. The process of manufacturing new cellulose derivatives, which are chemically alkyl ethers of cellulose which process consists in first treating cellulosic substances with suitable alkylating agents and secondly isolating the formed alkyl ethers of 1 cellulose from the reaction mixture, substantially as described.

2. The process of manufacturing new cellulose derivatives which are chemically alkyl ethers of cellulose which process consists in first treating cellulose derivatives which are soluble in a solution of an alkali with suitable alkylating agents and secondly isolating the formed alkyl ethers of cellulose from the reaction mixture, substantially as described- 3. The process of manufacturing new cellulose derivatives which... are chemically alkyl ethers of cellulose which process consists in first treating alkalinesolutions of cellulose derivatives which are soluble'in a solution of an alkali with suitable alkylating agents and secondly isolating the aileaeve Y formed alkyl ethers of cellulose from the ea reaction mixture, substantially as described.

4. Theprocess of manufacturing new cellulose derivatives wlnch are. chemically rocess concsters and secondly isolating the formed alkyl ethers of cellulose from the reaction mixture, substantially as described.

5. The process of manufacturing new cellulose derivatives which are chemically alkyl ethers of cellulose whic 1 process consists in first treating cellulosic substances with alkalis and inorganic alkyl esters and secondly isolating the formed alkyl ethers of cellulose from the reaction mixture, substantially as described.

6. The process of manufacturing new celv lulose derivatives which are chemically alkyl ethers of cellulose which process consists in first treating cellulosic' substances with alkalis and alkyl sulfates and secondly isolatingthe' formed alkyl ethers of cellulose from the reaction mixture, as described. 7 I

7.. The process of manufacturing new cellulose derivatives which 'are chemically alkyl ethers of cellulose which process consists in first, treating "cellulose derivatives which are solubleiin;a -solutionof an alkali with basic substances and inorganic alkyl esters and secondly isolating the formed alkyl ethers of cellulose from the' reaction mixture, substantially' as described.

8. 'The process ofmanufacturin new cellulose derivatives which are c emically alkyl ethers of cellulose which process-consists in first treating cellulose derivatives which are soluble in a solution of an alkali with alkalis and inorganic alkyl esters'and secondly isolating the formed alkyl ethers of cellulose from the reaction mixture, substantially as described.

' 9. The process of manufacturing new cellulose derivatives which are chemically alkyl ethers of cellulose which process consists in first treating cellulose derivatives which are soluble in a solution. of an alkali with alkal'is and alkyl'sulf'ates and secondly isolating the formed alkyl ethers of cellulose from the reaction mixture, substantially as cellulose derivatives which are soluble in asolution of an alkali with inorganic alkyl esters and secondly isolating the formed alkylethers of cellulose from the reaction mixture, substantially as described. 11. The process, of manufacturing new cellulose (ilerivatives which are chemically substantially Yalkyl ethers otcellulose which p consists in first treating alkaline solutions of cellulose derivatives'which are soluble in a solution of an alkali with alKalis and inoranic alkyl esters and secondly isolating the Y ormed alkyl ethers of cellulose from the reaction mix are, substantially as described. I

12. The process of manufacturing new cellulose derivatives which are chemically alkyl ethers of cellulose which process consists in first treating alkaline solutions of cellulose derivatives which are soluble in a solution of an alkali with alkyl sulfates and secondly isolating the formed alky-l ethers of cellulose from the reaction mixture, substantially as described,

I 13. The process of manufacturing new cellulose derivatives which are chemically alkyl ethers of cellulose which process consists in first treating alkaline solutions of cellulose derivatives which are soluble in a solution of an alkali with alkalis and alkyl sulfates and secondly isolating the formed" alkyl ethers of cellulose from the reaction mixture, substantially as described.

14. The process of manufacturing new cellulose derivatives which are chemically alkyl ethers of cellulose which process consists in first treating alkaline solutions ofcellulose derivatives which are solubl in a solution of an alkali with alkyl esters and secondly isolating the formed alkyl ethers of cellulose from the reaction mixture, substantially as described.

15. As new products, alkyl ethers of cellulose.

16. The process. of manufacturing new cellulose derivatives which are chemically ethyl ethers of cellulose which process consists in first treating cellulosic substances with ethylating agents and secondly isolattil ing the formed ethyl ethers of cellulose from the reaction mixture, substantially as described;

17. The process of manufacturing new cellulose derivatives which are chemically ethyl ethers of cellulose which process consists in first treating cellulose derivatives which are soluble'in a solution of an alkali with 'ethylating agents and secondly isolating the formed ethyl ethers of cellulose from the reaction mixture, substantially as described.

18. The process of manufacturing new cellulose derivatives which are chemically ethyl ethers of cellulose which process consists in first treating alkaline solutions of cellulose derivatives which are soluble in a solution of an alkali with suitable ethylatin agents and secondly isolating the formed ethyl ethers of cellulose from the re action mixture, substantially as described.

19. The process of manufacturing new cellulose derivatives which are chemically ethyl ethers of cellulose which process consists in first treating cellulosic substances with-basic substances and inorganic ethyl esters and secondly isolatingflth'e formed ethyl ethers of cellulose from the reaction mixture, substantially as described.

, 20. The process of manufacturing new quantity of an inorganic ethyl ester to convert the ethyl ether of cellulose soluble in water into an ethyl ether of cellulose insolucellulose derivatives which are chemically ble in water and finally isolating the formed ethyl ether of cellulose from the reaction mixture, substantially as described.

21. The process of manufacturing new cellulose derivatives which are chemically ethyl ethers of cellulose which process consists in first treating cellulosic substances with alkalis and. inorganic ethyl esters and secondly isolating the formed ethyl ethers stantially as described.

'22. The process of manufacturing new cellulose derivatives which are chemically alkyl etherspf cellulose which process consists in first treating cellulosic substances with-an alkali and with only a. portion of the quantity of an inorganic alkyl ester which would be necessary to form a water insoluble alkyl ether of cellulose, thus forming a water-soluble alkyl ether of cellulose, secondly treating the reaction mixture con- .of cellulose from the reaction mixture, subtaining the water-soluble alkyl ether of cellulose with a further quantity of an alkali and with a further quantity of an inorganic alkyl ester to convert the alkyl ether of cellulose soluble in water into an alkyl ether of cellulose insoluble in water and finally isolating the formed alkyl ether of cellulose from the reactionmixture, substantially as described.

23. The process of manu iacturing new cellulose derivatives which e chemically ethyl ethers of cellulose which process consists in first treating cellulosic substances with alkalis and eth l sulfate and secondly isolating the formed? ethyl ethers of cellulose from the reaction mixture, substantially as described. 7

24. e process of manufacturing new cellulose derivatives which are chemically. ethyl ethers of cellulose which process consists in first treating cellulose derivatives which are soluble in' a solution of an alkali with alkalis and inorganic ethyl esters and secondly isolating the formed ethyl ethers 'of cellulose from the reaction; mixture, sub-.

stantially as described.

25. The process of manufacturing new cellulose derivatives which are chemically ethyl ethers of cellulose which process consists in first treating cellulosederivatives which are-soluble in a solution of an alkali with alkalis and ethyl sulfate and secondly isolating the formed ethyl ethers of cellulose from the reaction mixture, substantially as described.

26. The process of manufacturing new cellulose derivatives which are chemically ethyl ethers of cellulose which, process consists in first treating alkaline solutions of cellulose derivatives which are soluble in a solution of an alkali with inorganic ethyl esters and secondly isolating the formed ethyl ethers of cellulose. from the reaction mixture, substantially as described.

27.'The' process of manufacturing new cellulose derivatives which are chemically ethyl ethers of cellulose which process consists in first treating alkaline solutions of cellulose derivatives which are soluble in a solution of an alkali with alkalis and inorganic ethyl esters and secondly isolating t e formed ethyl ethers of cellulose from the reaction mixture, substantially as described. Y

28. The process of manufacturing new cellulose derivatives. which are chemically ethyl ethers of cellulose which process consists in first treating alkaline solutions of cellulose derivatives which are soluble in a solution of an alkali with ethyl sulfate and secondly isolating the formed ethyl ethers of cellulose from the reaction mixture, substantially as described.

29. The process of .manufacturing new cellulose derivatives which are chemically ethyl ethers of cellulose which process consists in first treating alkaline solutions of cellulose derivatives which are'soluble in a solution of an alkali with alkalis and ethyl sulfate and secondly isolating the formed ethyl ethers of cellulose from the-reaction mixture, substantially as described.

'30. The process of manufacturing new cellulose derivatives which are chemically ethyl ethers of cellulose which process consistsin first treating an alkaline solution of a derivative of cellulose whichis soluble a solution of an alkali with only a portion of the quantity of ethyl sulfatewhich would be necessary to form a water insoluble ethyl other of cellulose,' thus forming a watersoluble ethyl ether of cellulose, secondly treating the reaction mixture containing JbhG WatQf-i soluble ethyl ether of cellulose with a further quantity of a basic substance ethers of cellulose.-

nieasre tion of the quantity of alkyl sulfate which would be necessary to form a water-insoluble-alkyl ether of cellulose thus forming a water-soluble allcyl other of cellulose, secondly treating the reaction mixture containmg the water-soluble alkyl ether of cellulose with a further quantity of a basic substance by adding caustic alkali in solid form and with a further quantity of alkyl sulfate to convert the alkyl ether of cellulose soluble in water into an alkyl ether of cellulose insoluble in water and finally isolating the formed alkyl ether of cellulose from the reaction mixture, substantially as described. Y

32. As new products, ethyl ethers of cellulose.

33. As newproducts, such ethyl ethers of cellulose as are practically insoluble in hot water butsoluble in organic solvents.

3%. As new products, ethyl ethers of cellulose which are soluble in cold. water.

35. As new products, alkyl ethers of cellulose in the .iorm' of plastic celluloid-like masses and films which may be obtained by evaporating the solutions of the said alkyl 36.' As new roducts, ethyl ethers of eel.- lulose in the orm of'plastic celluloid-like masses and films which may be obtained by evaporating the solutions of the said ethyl ethers of cellulose.

37. As new products, ethyl ethers of cel- -lulose which are solublein organic solvents but practically insoluble in hot water in the form of plastic celluloid-like masses and filmswhich may be obtained by evaporat- Milli ing the solutions of the said ethyl ethers 11155 ofcellulose. I p

38. As new products, alkyl ethers of cellulosein solid form. a

39; As new products, alkyl ethers of cellulose, having at least a. portion of the hydroxyl hydrogens of the cellulose, replaced by alkyl radicals each containing a plurality of carbon atoms.

40. As new products, alkyl ethers of cellulose which are insoluble in hot water.

41. The process of manufacturing new cellulose derivatives which are chemically 1 alkyl ethers of cellulose, which procem commegs" prises first treating a cellulosic' substance with an alkali and an ester of an inorganic acid and an alkyl-alcohol containin a plurality of carbon atoms, and therea r iso- 'lating the alkyl ether of cellulose from the reaction mixture:

42. As a new material, a solid product, containing as its essential constituent, alkyl ethers of cellulose..

43. As new products, eth l ethers of cellulose which are practice ly insoluble in water, but soluble in organic solvents.

44. As new products, ethyl ethers of cellulose which are soluble in organic solvents, but practically insoluble .in water, in the form of plastic celluloid-like masses and films, which may be obtained by evaporatin the solution of the said ethyl ethers of ca lulose.

45. A film comprising as an ingredient thereof, a cellulose ether.

46. A water-insoluble film com rising as an ingredient thereof,an ethyl et er of cel- 47 A film composed of material containing an alkyl ether of cellulose which ispractically insoluble in water, but soluble -1ng others 0 stance containing as its essentialconstituent, a cellulose ether that is a cellulose derivative in which at least one of the hydrogen atoms of the hydroxyl ups-of the cellulose is replacedby an a l radical.

49. The herein described new plastic substance containing as-its essential constituent, a cellulose ether soluble in some organic solvents. 1

50. The herein described new plastic sub stance containing as its essential constituent a cellulose ether insoluble in water but soluble in some organic solvents. 51. Films, more articularly for photographic pur oses, c aracterized by containcellulosic substances that is to compounds of cellulosic substances in sa. which at least one of the hydroxyl-hydrov gens of the cellulose molecule, 1s rep aced by an alkyl radical substantially as described.

In testimony whereof I have signed my name to this specification 1n the presence of two subscribing witnesses.

De. LEON LILIENFELD. Witnesses:

Hnawm Wrmnnnmcn, AUoUs'r Fvaene. 

